On 7/29/24 05:36, Gareth de Vaux wrote:
On Mon 2024-07-29 (13:45), Ronald Klop wrote:
You do not provide much information on your system or upgrade method so I can't
predict other issues you might run into, but as far as ZFS is concerned I think
your upgrade should be fine.
Thanks. It's a ZFS on root system, raidz2, GENERIC kernel, Xeon E3-1220. I
upgrade with the standard
source rebuild procedure.
The bootcode is not touched by upgrading FreeBSD. Upgrading the bootcode is a
separate manual step.
And as long as you do not run "zpool upgrade" the ZFS bootcode and pools will
stay compatible.
Sure, I update the bootcode after installworld to keep things in sync. The
question is is there not
eg. a chance of downgrading features by going to an earlier dated 13.0-RELEASE
version and not being
able to boot. Yes before running zpool upgrade.
The boot code needs to be new enough to understand features of the
ZFS pools it needs to boot. I'm not aware of any incompatibilities with
eh boot loader booting older versions.
If you need the pool to be compatible with an older version of
FreeBSD, then you want to specify the relevant compatibility version or
don't upgrade the pool after creating it with said older version of FreeBSD.
You may be able to get past the initial limitations of compatibility
of a FreeBSD version to ZFS pools by installing sysutils/openzfs when it
is newer than what is in that FreeBSD version and compatible with the
older system. 12 isn't an officially supported FreeBSD version anymore,
but openzfs was available through ports for it.
If you want the pools to not be upgraded "accidentally" you can do something like "zpool
set compatibility=freebsd-12.4 <pool-name>".
Different compatibility versions can be found here:
# ls -l /usr/share/zfs/compatibility.d/
Thanks, I have no /usr/share/zfs directory though?
You also haven't upgraded to 13 yet. 13 switched from the solaris
forked ZFS code to openzfs which I think is when such compatibilities
are added. Upgrading to 13+ does not upgrade your zpool, running `zpool
upgrade` with a pool name or -a does and that is when a newer bootloader
that is compatible with the features is needed and when you won't be
able to use that pool on an older FreeBSD. If you install the port on 12
you will also have that compatibility list but under the /usr/local
equivalent path but you do not need to specify a compatibility to not
run a zpool upgrade.
Keep in mind that having ZFS as a kernel module from the ports tree
means you will want to keep it rebuilt+reinstalled when the kernel gets
upgraded or disable it before that next boot until you do so. Disabling
won't work if it is a root-on-zfs type of pool and if the next boot
doesn't have a compatible ZFS kernel module in base (such as upgrading
from one version of 12 to another version of 12, or upgrading to 13+ but
of a version with ZFS older than what was installed from ports and too
old to have support for all enabled/activate zpool features).
To rephrase: is it safer to go from
12.4-STABLE -> 13.3-STABLE, or
12.4-STABLE -> 13.0-RELEASE -> 13.3-STABLE
I'd just do the leap in one run unless seeing /usr/src/UPDATING give
any intermediate required step. The newer 13 releases and stable has
fixes that you will want. When following stable, I haven't grabbed
release versions in between; I usually haven't waited so long to go from
one major version to the next. 14 also brings some nice performance so
you may consider if you are able and want to go to it.
Off the top of my head an example was somewhere around FreeBSD 10(?)
where upgrading further required installing up to a certain version of
10 first due to compiler changes so that you had a compatible compiler
for building later versions. I didn't find out if that could be worked
around by having a newer compatible compiler installed from
ports/packages. Maybe there are similar gotchas I have forgotten about
for later versions but the UPDATING file should be checked.
